Coda File System

Re: still a bit confused about the VM,memory,swap RVM issue

From: Nix <nix_at_esperi.demon.co.uk>
Date: Sun, 14 Nov 1999 11:43:07 +0000 (GMT)
> An anonymous mmap is done for the size of the RVM data, which is then
> read into this chunk of memory. For 1GB of RVM data you need at least
> 1GB of VM, which translates into at least 1GB swap space.

I've been wondering about this for some time.

Why does RVM not do a *real* mmap (i.e. a non-anonymous one) for the RVM
data? Flushing to disk would then be nearly automatic, and scalability
would suddenly shoot up.

Or is there something I'm missing? (I haven't looked at the RVM code
much, so it could be really obvious...)

>                                 And the fact that the data is completely
> stored in both the rvm data file and on the swap, even if there are no
> differences between the two isn't very nice either.

Emphatically agreed!

-- 
`If both of these are true, Unix98 ptys are fully operational, and
 ready to destroy unarmed planets.' --- Richard Gooch
Received on 1999-11-14 08:27:35